Advertisements
Advertisements
Question
Can a galvanometer as such be used for measuring the current? Explain.
Advertisements
Solution
Yes a galvanometer can be used for measuring the current
Conversion of a galvanometer into an ammeter

A shunt (low resistance) is connected in parallel with a galvanometer.
`S=(I_g/(I-I_g))G`
Here,
I = total current in circuit
G = resistance of the galvanometer
S = resistance of the shunt
Ig = current through the galvanometer
RELATED QUESTIONS
Write the underlying principle of a moving coil galvanometer.
A circular coil of 250 turns and diameter 18 cm carries a current of 12A. What is the magnitude of magnetic moment associated with the coil?
Explain how moving coil galvanometer is converted into a voltmeter. Derive the necessary formula.
Write current sensitivity of a galvanomete S.I. unit.
State the principle of the working of a moving coil galvanometer, giving its labeled diagram ?
A coil of radius 10 cm and resistance 40 Ω has 1000 turns. It is placed with its plane vertical and its axis parallel to the magnetic meridian. The coil is connected to a galvanometer and is rotated about the vertical diameter through an angle of 180°. Find the charge which flows through the galvanometer if the horizontal component of the earth's magnetic field is BH = 3.0 × 10−5 T.
A multirange voltmeter can be constructed by using a galvanometer circuit as shown in figure. We want to construct a voltmeter that can measure 2V, 20V and 200V using a galvanometer of resistance 10Ω and that produces maximum deflection for current of 1 mA. Find R1, R2 and R3 that have to be used.

A voltmeter of variable ranges 3 V, 15 V, 150 V is to be designed by connecting resistances R1, R2, R3 in series with a galvanometer of resistance G = 20 Ω, as shown in Fig. The galvanometer gives full pass through its coil for 1 mA current i.e. "gives full pass through it's coil for 1 mA current". Then, the resistances R1, R2 and R3 (in kilo ohms) should be, respectively:

A moving coil galvanometer has 150 equal divisions. Its current sensitivity is 10-divisions per milliampere and voltage sensitivity is 2 divisions per millivolt. In order that each division reads 1 volt, the resistance in ohms needed to be connected in series with the coil will be ______.
A voltmeter has a range of 0 - 20 V and a resistance of 500 Q. Explain how can be used to measure voltages from 0 - 200 volt?
